EnvironmentalResearchWeb.org, Jul 22, 2008
Of all the renewable technologies, wave and tidal energy is currently the most expensive way of producing energy. But a project in the UK hopes to help this technology move along the learning curve and bring down costs.
When installed in 2010, Wave Hub will be the world’s first large-scale wave farm. Just off the coast of Cornwall in south-west England, Wave Hub will consist of four berths, each with a maximum capacity of 5 MW. These four berths will be connected to onshore electrical equipment via a 25 km long sub-sea cable. The water at the deployment site is approximately 50 metres deep and the project will cover an area of sea measuring 4 km by 2 km.
Wave Hub is designed to be a place where companies and researchers can develop and test their marine energy devices as a final stage towards commercialisation. Each wave device developer will be granted a lease of between five and 10 years in an area of approximately two square kilometres. The total number of devices to be deployed at Wave Hub is not expected to exceed 30.
“Getting planning consent for marine energy devices can be a lengthy and challenging process which often slows down their development,” says Nick Harrington, general manager for the Wave Hub project at the South West Regional Development Agency (SWRDA). “Wave Hub provides companies with a consented sea area in which to test their devices. It also provides a grid connection, monitoring and testing support, a power purchase agreement, access to suppliers and a research base, and opportunities to collaborate with other companies.”
In order to get planning consent for Wave Hub, the SWRDA carried out a detailed environmental impact assessment. This involved an analysis of the potential impacts of the project on different parts of the environment. This includes the effects of laying the cable (most of which will be offshore) and the impacts of the likely arrays of wave energy devices on marine ecology, fisheries, recreational users and navigation.
“The environmental impact of the Wave Hub will be much lower than other proposed schemes such as the Severn Tidal Barrage,” says Harrington. “The devices float on the water and will have very little impact on waves reaching the shore. There will be very little terrestrial land-take, with only one cable coming ashore, terminating near the site of a disused power station.”
Harrington believes the construction of Wave Hub could be very quick, taking about eight weeks to complete, but admits there are still some major challenges ahead before Wave Hub is finally installed. “We are conscious that the economic environment is quite challenging. The rising cost of oil has led to a boom in oil and gas exploration, which has increased substantially the cost of hiring vessels needed to install Wave Hub. Volatile markets have also seen significant increases in the cost of copper, which has increased the cost of the cable that will be laid between Wave Hub and the mainland.”
The first four berths have already been allocated to Oceanlinx, Ocean Power Technologies, Fred Olsen and WestWave, a consortium of E.On and Ocean Prospect.
“Wave and tidal energy is currently in the same position on the learning curve that wind energy was a few years ago,” says Harrington. “Doing anything at sea is costly and difficult but Wave Hub will help companies bring those costs down and help make wave energy a viable renewable energy solution for the future. The UK has one of the largest wave energy resources in Europe. Allowing for technical, practical and environmental limitations, according to The Carbon Trust, wave energy could generate up to one sixth of the UK’s electricity consumption. By 2020 the wave energy market in the UK could by worth £0.2 billion.”